[C320-list] Crack Between Hull and Keel

[Dave Hupe]

I just became the new owner of a 1994 (built 1993) Cat 320 (Hull 32 with wing keel). Prior to lifting the boat from its cradle and putting the boat back in the water for this new season, I did some substantial repairs to the hull/keel interface and retightened the keel bolts.

There was some significant cracking at the hull/keel interface, not all the way around the keel, but particularly at the aft end. I cleaned out all the loose/cracked areas by scraping, sanding and using a Dremel tool until the surrounding layers were firm (even down to the lead on the keel where necessary).  I then retightened the keel bolts. After cleaning with acetone/alcohol, I then used Pettit FlexPoxy to fill the areas that I cleaned out, since this material is purported to retain some flexibility.  I used Pettit Protect primer over the repair areas and then applied antifouling. 

To my dismay, upon lifting the boat with slings from the cradle to launch the boat (thus all the weight of the keel hanging again), the keel seemed to sag at the aft end and the FlexPoxy cracked open (several inches long horizontally and up to about 1/4 inch gap) at the aft end of the keel. 

After launching, I was concerned that I was getting leakage of water from the keel bolts into the shallow bilge.  However, after monitoring this closely for several days, the water may actually have been primarily water that leaked at a new packing gland I also had installed before launch (and got into the hollow floor grid and slowly bled up into the bilge). 

Has anyone else (low hull numbers with shallow bilge) experienced anything similar about their keel?  What have you done to repair this, so that there isn't a perpetual big/open crack at the hull/keel interface?  

My local marina service shop is suggesting hauling the boat back out of the water and leaving it suspended in slings while the keel hangs (therefore maximum open crack).  They then are proposing cleaning out the (open) crack again, filling with epoxy, and also doing fiberglass over the newly filled area (lapping between the hull and keel) to reinforce this.

Dave Hupe
1994 Hull #32  
Holland, MI